- 1(current)
Q. No.Assertion(A): It is the metabolic, physiological, or environmental conditions that regulate the expression of genes.
Reason(R): if the bacteria do not have lactose, they would no longer require the synthesis of the enzyme beta-galactosidase.
Choices for Assertions and reasons:
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Reason(R): if the bacteria do not have lactose, they would no longer require the synthesis of the enzyme beta-galactosidase.
Choices for Assertions and reasons:
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic: Â Gene Regulation: Lac Operon |
 58%
From NCERT
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Assertion(A): Only two structural gene products in lac operon are required for metabolism of lactose.
Reason(R): The y gene codes for permease, which increases permeability of the cell to b-galactosides.
Choices for Assertions and reasons:
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Reason(R): The y gene codes for permease, which increases permeability of the cell to b-galactosides.
Choices for Assertions and reasons:
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic: Â Gene Regulation: Lac Operon |
 76%
From NCERT
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Assertion(A): Lactose is termed as inducer.
Reason(R): It regulates switching on and off of the operon.
Choices for Assertions and reasons:
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Reason(R): It regulates switching on and off of the operon.
Choices for Assertions and reasons:
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic: Â Gene Regulation: Lac Operon |
 87%
From NCERT
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Hints
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Assertion(A): It is the metabolic, physiological, or environmental conditions that regulate the expression of genes.
Reason(R): In the absence of lactose, the beta-galactosidase enzyme is synthesized by E. coli.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Reason(R): In the absence of lactose, the beta-galactosidase enzyme is synthesized by E. coli.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic: Â Gene Regulation: Introduction |Â Gene Regulation: Lac Operon |
 79%
From NCERT
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Assertion(A): Lac operon regulation is a kind of regulation of enzyme synthesis by its substrate.
Reason(R): Lac operon is regulated by the presence of glucose in the medium which acts as an inducer.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Reason(R): Lac operon is regulated by the presence of glucose in the medium which acts as an inducer.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic: Â Gene Regulation: Lac Operon |
 81%
From NCERT
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Hints
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- 1(current)
Q. No.
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